Copper could be a major environmental culprit in the progression of Alzheimer’s, research suggests.
Scientists found strong evidence that copper helps to promote the changes in the brain, which may both cause and exacerbate the disease. But they conclude there is little that can be done about it, as copper is so abundant in the diet and also vital to health. The metal, found in food and drinking water, plays important roles in nerve function, bone growth, the formation of connective tissue, and hormone secretion.
Researchers in the US conducted a series of experiments on mice given trace amounts of copper in their drinking water. In human terms, the doses were equivalent to the amount of copper people consume in a normal diet, and about a tenth of what is allowed under US water quality standards.
The study showed that copper accumulating in the brain disrupted the natural removal of toxic amyloid beta protein, which is strongly implicated in Alzheimer’s. Copper also directly stimulated neurons that increased the production of amyloid beta, and caused the proteins to clog together in lumps that could not be cleared.
“It is clear that, over time, copper’s cumulative effect is to impair the systems by which amyloid beta is removed from the brain,” said study leader Professor Rashid Deane, from the University of Rochester Medical Centre in New York. The findings were reported in the journal Proceedings of the National Academy of Sciences.
Dr Doug Brown, of the Alzheimer’s Society, said the study was only “early research”. He added: “Considering copper is a vital mineral, people should treat these results with caution and not cut it out of their diet.”